Republicans have found a boatload of reasons to try to sink Chuck Hagel's hopes of becoming the next defense secretary. But the issue they last used to stall his nomination — the White House's handling of last September's deadly Benghazi attack — may seem entirely unrelated to Hagel's qualifications because, well, it is.

Here are some questions and answers about the connection between President Obama's choice to lead the Pentagon and the campaign by Sen. John McCain and others in the Senate to press for more answers on Benghazi:

Q: How did the Hagel nomination become entangled with Benghazi?

A: The short answer is politics. Hagel had no role in the crisis that took the lives of four Americans, including Ambassador Chris Stevens. Neither did the Pentagon, although some have questioned why U.S. troops did not reach Libya until well after the crisis was over. The answer from Defense Secretary Leon Panetta is that the closest relevant U.S. forces could not get there before the killings; he has said the Pentagon could have acted sooner if it had received intelligence warnings in advance of the attack.

Sen. Lindsey Graham, the South Carolina Republican who has joined McCain, R-Ariz., in temporarily blocking the Hagel nomination, does not claim a connection between the two issues. He asserts that Obama was inattentive when the Benghazi emergency was unfolding, and that by keeping a public focus on this, the Benghazi experience could be a teaching tool for future presidents. Graham, in other words, is using Hagel as a political wedge to highlight what he sees as an exploitable Obama failure.

Q: What remains to be uncovered about the administration's handling of the Benghazi attack?

A: In a nutshell, McCain, Graham and other Republicans say the White House needs to explain more fully why the four Americans died and what the president's role was in coordinating a response by the Pentagon and State Department. The White House says it has answered all ­relevant questions. Last week, the White House responded to a Republican request that it say whether Obama spoke to anyone in the Libyan government on the day of the attack, Sept. 11, to request assistance for the trapped Americans. The answer, which had been stated previously, was that Obama called Libyan President Mohamed Magariaf on the evening of Sept. 12, and that then-Secretary of State Hillary Rodham Clinton phoned Magariaf on Obama's behalf on Sept. 11.

Q: Are there more substantive reasons for Republicans' opposition to Hagel?

A: Yes. They start with an assertion that Hagel is insufficiently supportive of Israel and unreasonably sympathetic to Iran. And Republicans dislike Hagel's association with an international movement called Global Zero, which advocates for sharp reductions in the number of U.S. nuclear weapons and an eventual elimination of them worldwide. McCain has hammered Hagel for "a disqualifying lack of professional judgment."

Hagel and the White House insist he is well qualified, in part on the basis of his experience in the Senate, his work in the private sector, and his record as a decorated Vietnam combat veteran. "For the sake of national security, it's time to stop playing politics with our Department of Defense, and to move beyond the distractions and delay," the White House press secretary, Jay Carney, said.

Associated Press